Electrically driven separations processes for analysis of complex mixtures have become widely accepted throughout the field of biotechnology, and electrophoresis-based devices continue to find widespread use in on-going proteomic investigations. The most prominent technique for proteomic analysis of complex mixtures employs two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), where a complex mixture is loaded onto a gel and resolved along a first axis using isoelectric focusing (i.e., resolving components according to pI) and then along a second axis using SDS-PAGE (i.e., resolving molecules based upon molecular weight). The popularity of electrophoresis stems from the technique's ability to resolve target molecules on the basis of small differences in molecular weight, electrophoretic mobilities, isoelectric points, or combinations of these properties. Although successful, PAGE-based techniques can be time consuming, labor intensive, and do not allow for easy recovery of sample or adjustment of sample loadings to compensate for maldistribution of components commonly observed in biological systems. In addition, integration of 2D-PAGE systems into seamless analytical systems is oftentimes cumbersome.
Chromatographic techniques for analysis of complex mixtures are second only to electrophoresis techniques in terms of resolving power and are more amenable to automation and hyphenation. However, sample concentration issues, flowrate dissimilarities, time-scale differences, or an ability to perform in situ buffer exchange are problematic when integrating LC techniques into hyphenated instrument platforms.
Thus, there is a need for electrically-driven separation devices, systems and methods, suitable for separating and/or concentrating charged analytes, especially for separation and concentration of biomacromolecules, for example, proteins. Accordingly, it is an object of this invention to provide devices, systems and methods for separation and/or concentration of charged analytes.